[PATCH 01/11] i2c: imx-lpi2c: directly retrun ISR when detect a NACK
From: Clark Wang <xiaoning.wang@nxp.com>
Date: 2021-03-17 06:54:56
Also in:
linux-arm-kernel, lkml
Subsystem:
freescale imx lpi2c driver, i2c subsystem, i2c subsystem host drivers, the rest · Maintainers:
Dong Aisheng, Andi Shyti, Linus Torvalds
From: Gao Pan <redacted> A NACK flag in ISR means i2c bus error. In such codition, there is no need to do read/write operation. It's better to return ISR directly and then stop i2c transfer. Signed-off-by: Gao Pan <redacted> Signed-off-by: Clark Wang <xiaoning.wang@nxp.com> --- drivers/i2c/busses/i2c-imx-lpi2c.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-)
diff --git a/drivers/i2c/busses/i2c-imx-lpi2c.c b/drivers/i2c/busses/i2c-imx-lpi2c.c
index 9db6ccded5e9..bbf44ac95021 100644
--- a/drivers/i2c/busses/i2c-imx-lpi2c.c
+++ b/drivers/i2c/busses/i2c-imx-lpi2c.c@@ -507,15 +507,17 @@ static irqreturn_t lpi2c_imx_isr(int irq, void *dev_id) lpi2c_imx_intctrl(lpi2c_imx, 0); temp = readl(lpi2c_imx->base + LPI2C_MSR); + if (temp & MSR_NDF) { + complete(&lpi2c_imx->complete); + goto ret; + } + if (temp & MSR_RDF) lpi2c_imx_read_rxfifo(lpi2c_imx); - - if (temp & MSR_TDF) + else if (temp & MSR_TDF) lpi2c_imx_write_txfifo(lpi2c_imx); - if (temp & MSR_NDF) - complete(&lpi2c_imx->complete); - +ret: return IRQ_HANDLED; }
--
2.25.1